1. Field of the Invention:
The present invention relates to an infrared data communication module used for performing infrared data communication by IrDA (Infrared Data Association) method. The present invention also relates to a method for making such an infrared data communication module.
2. Description of the Related Art:
Infrared data communication modules are conventionally utilized for performing infrared data communication based on the IrDA (Infrared Data Association) method between different apparatuses such as notebook-size personal computers or mobile phones or between such an apparatus and a peripheral device such as a printer. A prior art infrared data communication module (hereinafter simply referred to as “module”) has such a structure as shown in FIGS. 12 and 13. Specifically, the module 1 includes a substrate 3 having a surface 3a formed with a conductor pattern 2, a light emitting element 4, a light receiving element 5, and an IC element 6 mounted at predetermined portions of the conductor pattern 2. The elements 4, 5, 6 are connected, via gold wires W, to predetermined portions of the conductor pattern 2.
The surface 3a of the substrate 3 is upwardly provided with a package 9 formed by molding a resin for integrally sealing the elements 4, 5, and 6. The package 9 has an upper surface 9a formed with a light emitting lens 11 at a location corresponding to the light emitting element 4 and a light receiving lens 12 at a location corresponding to the light receiving element 5. The substrate 3 has a lower surface 3b formed with connection terminals 13 (See FIG. 12) for connection to an external circuit board (not shown) by soldering. The substrate 3 has a side surface 3c formed with grooves 14 for electrically connecting the connection terminals 13 to the conductor pattern 2 on the upper surface 3a of the substrate 3.
In use, the module 1 having the above-described structure is mounted onto a circuit board (not shown) for incorporation in an electronic apparatus (not shown) such as a notebook-size personal computer or a mobile phone.
However, in using the module 1 as a part of such an electronic apparatus, the IC element 6 may be adversely affected by noises generated internally or externally of the apparatus. The internal noises may come from the power source of the apparatus, whereas external noises may include electromagnetic waves (other than light), light from a fluorescent lamp or the sunlight.
The IC element 6 may incorporate an electronic circuit for avoiding the influences of the noises caused by electromagnetic waves. Generally, however, such a circuit is not effective for avoiding the influences of light.
Therefore, as shown in FIG. 14, the module maybe provided with a metallic shield case 28 for blocking light. By the shield case 28, the IC element 6 can be prevented from erroneously operating due to the noises caused by light.
However, the provision of the shield case 28 increases the parts cost of the module 1. Moreover, the process step of attaching a shield case 28 to a module 1 one by one increases the manufacturing cost.